" File: AutoFenc.vim
" Brief: Tries to automatically detect file encoding
" Author: Petr Zemek, s3rvac AT gmail DOT com
" Version: 1.3.2
" Last Change: Thu Nov 24 14:06:00 CET 2011
"
" License:
" Copyright (C) 2009-2011 Petr Zemek
" This program is free software; you can redistribute it and/or modify it
" under the terms of the GNU General Public License as published by the Free
" Software Foundation; either version 2 of the License, or (at your option)
" any later version.
"
" This program is distributed in the hope that it will be useful, but
" WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
" or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
" for more details.
"
" You should have received a copy of the GNU General Public License along
" with this program; if not, write to the Free Software Foundation, Inc.,
" 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
"
" Description:
" This script tries to automatically detect and set file encoding when
" opening a file in Vim. It does this in several possible ways (according
" to the configuration) in this order (when a method fails, it tries
" the following one):
" (1) detection of BOM (byte-order-mark) at the beginning of the file,
" only for some multibyte encodings
" (2) HTML way of encoding detection (via tag), only for HTML based
" file types
" (3) XML way of encoding detection (via declaration), only
" for XML based file types
" (4) CSS way of encoding detection (via @charset 'at-rule'), only for
" CSS files
" (5) checks whether the encoding is specified in a comment (like
" '# Encoding: latin2'), for all file types
" (6) tries to detect the encoding via specified external program
" (the default one is enca), for all file types
"
" If the autodetection fails, it's up to Vim (and your configuration)
" to set the encoding.
"
" Configuration options for this plugin (you can set them in your $HOME/.vimrc):
" - g:autofenc_enable (0 or 1, default 1)
" Enables/disables this plugin.
" - g:autofenc_emit_messages (0 or 1, default 0)
" Emits messages about the detected/used encoding upon opening a file.
" - g:autofenc_max_file_size (number >= 0, default 10485760)
" If the size of a file is higher than this value (in bytes), then
" the autodetection will not be performed.
" - g:autofenc_disable_for_files_matching (regular expression, see below)
" If the file (with complete path) matches this regular expression,
" then the autodetection will not be performed. It is by default set
" to disable autodetection for non-local files (e.g. accessed via ftp,
" scp etc., because the script can't handle some kind of autodetection
" for these files). The regular expression is matched case-sensitively.
" - g:autofenc_disable_for_file_types (list of strings, default [])
" If the file type matches some of the filetypes specified in this list,
" then the autodetection will not be performed. Comparison is done
" case-sensitively.
" - g:autofenc_autodetect_bom (0 or 1, default 0 if 'ucs-bom' is in
" 'fileencodings', 1 otherwise)
" Enables/disables detection of encoding by BOM.
" - g:autofenc_autodetect_html (0 or 1, default 1)
" Enables/disables detection of encoding for HTML based documents.
" - g:autofenc_autodetect_xml (0 or 1, default 1)
" Enables/disables detection of encoding for XML based documents.
" - g:autofenc_autodetect_css (0 or 1, default 1)
" Enables/disables detection of encoding for CSS documents.
" - g:autofenc_autodetect_comment (0 or 1, default 1)
" Enables/disables detection of encoding in comments.
" - g:autofenc_autodetect_num_of_lines (number >= 0, default 5)
" How many lines from the beginning and from the end of the file should
" be searched for the possible encoding declaration.
" - g:autofenc_autodetect_ext_prog (0 or 1, default 1)
" Enables/disables detection of encoding via external program
" (see additional settings below).
" - g:autofenc_ext_prog_path (string, default 'enca')
" Path to the external program. It can be either relative or absolute.
" The external program can take any number of arguments, but
" the last one must be a path to the file for which the encoding
" is to be detected (it will be supplied by this plugin).
" Output of the program must be the name of encoding in which the file
" is saved (string on a single line).
" - g:autofenc_ext_prog_args (string, default '-i -L czech')
" Additional program arguments (can be none, i.e. '').
" - g:autofenc_ext_prog_unknown_fenc (string, default '???')
" If the output of the external program is this string, then it means
" that the file encoding was not detected successfully. The string must
" be case-sensitive.
"
" Requirements:
" - filetype plugin must be enabled (a line like 'filetype plugin on' must
" be in your $HOME/.vimrc [*nix] or %UserProfile%\_vimrc [MS Windows])
"
" Installation Details:
" Put this file into your $HOME/.vim/plugin directory [*nix]
" or %UserProfile%\vimfiles\plugin folder [MS Windows].
"
" Notes:
" This script is by all means NOT perfect, but it works for me and suits my
" needs very well, so it might be also useful for you. Your feedback,
" opinion, suggestions, bug reports, patches, simply anything you have
" to say is welcomed!
"
" There are similar plugins to this one, so if you don't like this one,
" you can test these:
" - FencView.vim (http://www.vim.org/scripts/script.php?script_id=1708)
" Mainly supports detection of encodings for asian languages.
" - MultiEnc.vim (http://www.vim.org/scripts/script.php?script_id=1806)
" Obsolete, merged with the previous one.
" - charset.vim (http://www.vim.org/scripts/script.php?script_id=199)
" Not very complete/correct and last update in 2002.
" - http://vim.wikia.com/wiki/Detect_encoding_from_the_charset_specified_in_HTML_files
" Same basic ideas but only for HTML files.
" Let me know if there are others and I'll add them here.
"
" Changelog:
" 1.3.2 (2011-11-24) Thanks to Benjamin Fritz for the updates in this version.
" - Fixed the detection of the version of the TOhtml plugin.
"
" 1.3.1 (2011-07-23) Thanks to Benjamin Fritz for the updates in this version.
" - Fixed the plugin behavior when reloading a file with different settings.
"
" 1.3 (2011-04-22) Thanks to Benjamin Fritz for the updates in this version.
" - Added support for HTML version 5 encoding detection.
" - The script now dies gracefully in old Vims.
" - 'g:autofenc_autodetect_comment_num_of_lines' renamed to 'g:autofenc_autodetect_num_of_lines'
"
" 1.2.1 (2011-04-13)
" - Fixed a typo in a variable name (this resulted in an error in some
" occasions). Thanks to Charles Lee for pointing this bug out.
"
" 1.2 (2011-03-31) Thanks to Benjamin Fritz for the updates in this version.
" - TOhtml's IANA name/Vim encoding conversion functions are now used.
" - Changed BOM detection so it does not duplicate a check Vim already did by
" default (i.e. default to off if ucs-bom is in the 'fileencodings').
" - Put autocmds in the AutoFenc augroup for easier handling.
" - Made autocmd nested so we don't need to worry about restoring everything
" that other autocmds may set (e.g. syntax).
" - Jumplist or cursor position during detection are not affected.
" - The g:autofenc_autodetect_num_of_lines option is now used also in
" HTML/XML/CSS detection routines (previously only used for encoding
" specified in comments).
" - Improved HTML charset line regex.
" - Added an option (g:autofenc_emit_message) to emit messages about the
" detected/used encoding upon opening a file.
"
" 1.1.1 (2009-10-03)
" - Fixed the comment encoding detection function (the encoding was not
" detected if there were some alphanumeric characters before
" the "encoding" string, like in "# vim:fileencoding=").
"
" 1.1 (2009-08-16)
" - Added three configuration possibilites to disable autodetection for
" specific files (based on file size, file type and file path).
" See script description for more info.
"
" 1.0.2 (2009-08-11)
" - Fixed the XML encoding detection function.
" - Minor code and documentation fixes.
"
" 1.0.1 (2009-08-02)
" - Encoding autodetection is now performed only if the opened file
" exists (is stored somewhere). So, for example, the autodetection
" is now not performed when a new file is opened.
" - Correctly works with .viminfo, where the last cursor position
" in the file is stored when exiting the file. In the previous version
" of this script, this information was sometimes ignored and the cursor
" was initially on the very last line in a file. If the user does not
" use this .viminfo feature (or he does not use .viminfo at all),
" then the cursor will be initially placed on the very first line.
" - (Hopefully) fixed the implementation of the function which sets
" the detected encoding.
"
" 1.0 (2009-07-26)
" - Initial release version of this script.
"
" Check if the plugin was already loaded. Also, die gracefully if the used Vim
" version is too old.
if exists('autofenc_loaded') || v:version < 700
finish
endif
" make the loaded variable actually useful by including the version number
let autofenc_loaded = '1.3'
"-------------------------------------------------------------------------------
" Checks whether the selected variable (first parameter) is already set and
" if not, it sets it to the value of the second parameter.
"-------------------------------------------------------------------------------
function s:CheckAndSetVar(var, value)
if !exists(a:var)
exec 'let ' . a:var . ' = ' . string(a:value)
endif
endfunction
" Variables initialization (see script description for more information)
call s:CheckAndSetVar('g:autofenc_enable', 1)
call s:CheckAndSetVar('g:autofenc_emit_messages', 0)
call s:CheckAndSetVar('g:autofenc_max_file_size', 10485760)
call s:CheckAndSetVar('g:autofenc_disable_for_files_matching', '^[-_a-zA-Z0-9]\+://')
call s:CheckAndSetVar('g:autofenc_disable_for_file_types', [])
call s:CheckAndSetVar('g:autofenc_autodetect_bom', (&fileencodings !~# 'ucs-bom'))
call s:CheckAndSetVar('g:autofenc_autodetect_html', 1)
call s:CheckAndSetVar('g:autofenc_autodetect_xml', 1)
call s:CheckAndSetVar('g:autofenc_autodetect_css', 1)
call s:CheckAndSetVar('g:autofenc_autodetect_comment', 1)
call s:CheckAndSetVar('g:autofenc_autodetect_num_of_lines', 5)
call s:CheckAndSetVar('g:autofenc_autodetect_ext_prog', 1)
call s:CheckAndSetVar('g:autofenc_ext_prog_path', 'enca')
call s:CheckAndSetVar('g:autofenc_ext_prog_args', '-i -L czech')
call s:CheckAndSetVar('g:autofenc_ext_prog_unknown_fenc', '???')
"-------------------------------------------------------------------------------
" Normalizes selected encoding and returns it, so it can be safely used as
" a new encoding. This function should be called before a new encoding is set.
"-------------------------------------------------------------------------------
function s:NormalizeEncoding(enc)
let nenc = tolower(a:enc)
" Recent versions of TOhtml runtime plugin have some nice charset to encoding
" functions which even allow user overrides. Use them if available.
if has('float') && exists('g:loaded_2html_plugin') &&
\ (str2float(strpart(g:loaded_2html_plugin, 3)) >= 7.3 ||
\ str2float(strpart(g:loaded_2html_plugin, 3)) == 7.3 &&
\ str2nr(substitute(g:loaded_2html_plugin, '.*_v', '', '')) >= 7)
let nenc2 = tohtml#EncodingFromCharset(nenc)
if nenc2 == ""
if g:autofenc_emit_messages
echomsg 'AutoFenc: detected unrecognized charset, trying fenc='.nenc
endif
else
return nenc2
endif
" If TOhtml is unavailable or the wrong version, at least handle some
" canonical encoding names in Vim.
elseif nenc =~ 'iso[-_]8859-1'
return 'latin1'
elseif nenc =~ 'iso[-_]8859-2'
return 'latin2'
elseif nenc ==? 'gb2312'
return 'cp936' " GB2312 imprecisely means CP936 in HTML
elseif nenc =~ '\(cp\|win\(dows\)\?\)-125\d'
return 'cp125'.nenc[strlen(nenc)-1]
elseif nenc == 'utf8'
return 'utf-8'
endif
return nenc
endfunction
"-------------------------------------------------------------------------------
" Sets the selected file encoding. Returns 1 if the file was reloaded,
" 0 otherwise.
"-------------------------------------------------------------------------------
function s:SetFileEncoding(enc)
let nenc = s:NormalizeEncoding(a:enc)
" Check whether we're not trying to set the current file encoding
if nenc != "" && nenc !=? &fenc
" Set the file encoding and reload it, keeping any user-specified
" fileformat, and keeping any bad bytes in case the header is wrong (this
" won't let the user save if a conversion error happened on read)
exec 'edit ++enc='.nenc.' ++ff='.&ff.' ++bad=keep'
" File was reloaded
return 1
else
" File was not reloaded
return 0
endif
endfunction
"-------------------------------------------------------------------------------
" Tries to detect a BOM (byte order mark) at the beginning of the file to
" detect a multibyte encoding. If there is a BOM, it returns the appropriate
" encoding, otherwise the empty string is returned.
"-------------------------------------------------------------------------------
function s:BOMEncodingDetection()
" Implementation of this function is based on a part of the FencsView.vim
" plugin by Ming Bai (http://www.vim.org/scripts/script.php?script_id=1708)
" Get the first line of the file
let file_content = readfile(expand('%:p'), 'b', 1)
if file_content == []
" Empty file
return ''
endif
let first_line = file_content[0]
" Check whether it contains BOM and if so, return appropriate encoding
" Note: If the index is out of bounds, ahx is set to '' automatically
let ah1 = first_line[0]
let ah2 = first_line[1]
let ah3 = first_line[2]
let ah4 = first_line[3]
" TODO: I don't know why but if there is a NUL byte, the char2nr()
" function transforms it to a newline (0x0A) instead of 0x00...
let a1 = char2nr(ah1) == 0x0A ? 0x00 : char2nr(ah1)
let a2 = char2nr(ah2) == 0x0A ? 0x00 : char2nr(ah2)
let a3 = char2nr(ah3) == 0x0A ? 0x00 : char2nr(ah3)
let a4 = char2nr(ah4) == 0x0A ? 0x00 : char2nr(ah4)
if a1.a2.a3.a4 == 0x00.0x00.0xfe.0xff
return 'utf-32'
elseif a1.a2.a3.a4 == 0xff.0xfe.0x00.0x00
return 'utf-32le'
elseif a1.a2.a3 == 0xef.0xbb.0xbf
return 'utf-8'
elseif a1.a2 == 0xfe.0xff
return 'utf-16'
elseif a1.a2 == 0xff.0xfe
return 'utf-16le'
endif
" There was no legal BOM
return ''
endfunction
"-------------------------------------------------------------------------------
" Tries the HTML way of encoding detection of the current file and returns the
" detected encoding (or the empty string, if the encoding was not detected).
"-------------------------------------------------------------------------------
function s:HTMLEncodingDetection()
" This method is based on the meta tag in the head of the HTML document
" ()
" Store the actual position in the file and move to the very first line
" in the file
let curpos=getpos('.')
keepjumps 1
let enc = ''
let charset_line = search('\c g:autofenc_max_file_size || file_size < 0 ||
\ file_path =~ g:autofenc_disable_for_files_matching ||
\ index(g:autofenc_disable_for_file_types, &ft, 0, 1) != -1
return ''
endif
" BOM encoding detection
if g:autofenc_autodetect_bom
let enc = s:BOMEncodingDetection()
if enc != ''
return enc
endif
endif
" HTML encoding detection
if g:autofenc_autodetect_html && &filetype =~ '\(html\|xhtml\)'
let enc = s:HTMLEncodingDetection()
if enc != ''
return enc
endif
endif
" XML encoding detection
if g:autofenc_autodetect_xml && &filetype =~ '\(xml\|xsl\|xsd\)'
let enc = s:XMLEncodingDetection()
if enc != ''
return enc
endif
endif
" CSS encoding detection
if g:autofenc_autodetect_css && &filetype =~ '\(css\)'
let enc = s:CSSEncodingDetection()
if enc != ''
return enc
endif
endif
" Comment encoding detection
if g:autofenc_autodetect_comment
let enc = s:CommentEncodingDetection()
if enc != ''
return enc
endif
endif
" External program encoding detection
if g:autofenc_autodetect_ext_prog
let enc = s:ExtProgEncodingDetection()
if enc != ''
return enc
endif
endif
" Encoding was not detected
return ''
endfunction
"-------------------------------------------------------------------------------
" Main plugin function. Tries to autodetect the correct file encoding
" and sets the detected one (if any). If the ASCII encoding is detected,
" it does nothing so allow Vim to set its internal encoding instead.
"-------------------------------------------------------------------------------
function s:DetectAndSetFileEncoding()
let enc = s:DetectFileEncoding()
" don't call again on the nested trigger from the edit
let b:autofenc_done = enc
if (enc != '') && (enc != 'ascii')
if s:SetFileEncoding(enc)
if g:autofenc_emit_messages
echomsg "AutoFenc: Detected [".enc."] from file, loaded with fenc=".&fenc
endif
endif
endif
endfunction
" Set the detected file encoding
if g:autofenc_enable
augroup AutoFenc
au!
" We need to check that we're not in the middle of a reload due to this
" plugin otherwise can recurse forever. But unlet the variable to allow
" re-detection on the next read of this buffer if it is just unloaded.
au BufRead * nested if !exists('b:autofenc_done') | call s:DetectAndSetFileEncoding() | else | unlet b:autofenc_done | endif
augroup END
endif
" vim: noet